Oily composition



Patented Dec. 7, 1948 Gordon W. Duncan, mer, Union, N. J

assi Development Company, ware Westfleld, and John C. Zimgnors to Standard Oil a corporation of Dela- No Drawing. Application October 5, 1945,

Serial No. 620,630

l Claim. (cl. 252-33) The present invention relates to a method of T producing improved oily compositions which may be used for many purposes, and especially to improvements in such oils by giving to them greater ability to protect metals, with which they are in contact, from corrosion caused by contamination of the oily composition with moisture. The invention contemplates not only the method of producing the oils, but the new compositions themselves.

selected with a view to the particular use intended, that is to say, its flash point, viscosity and the like must be adapted to the Just as it is done at the present time.

To this 011 base is then added from 0.05 to 10.0%, depending upon contemplated use of the product, of an oil-soluble sulfonate salt which of metals. These compositions are normally sup plied by the manufacturers as oils and are diluted Nevmany cases, oils do permit a minor form of spotting or discoloring and the object of invention is to remove this deficiency. Still other oils are employed for general or surfaces caused by water oils.

The present invention deals with the improvement of all such oils in this particular direction. It is also highly desirable that these oils should be clear, free from any sediment and suited to the intended purpose.

Inmaking the present compositions, it will be understood from what has been said before that there is an oily vehicle which comprises the major portion of the present composition. This may be an oil of vegetable, animal or mineral origin. The common fatty oils such as castor oil, lard oil and the like may, of hydrocarbon oils are particularly to be desired, whether they are derived from asphaltic, vmixed base or parafllnic crudes, and the oil must be on the other hand, to submerge" inhibiting properties when dissolved in water. Various inorganic salts .of this type are known generally known as M 'ried out in the following An aqueous solution of the inorganic compound is well known to the petroleum art and is obtained as a by-product in the refining of mineral oils, particularly lubricating oils, with concentrated or fuming sulfuric acid. Alkali and alkaline earth metal sulfonates are normally preferred but other metal and nitrogen base sulfonates may be employed. The particular sulfonate is of the type soap or "mahogany soap and is also known as the oil-soluble sulfonate to distinguish it from the so-called green acid soaps which are water-soluble. It is usually available as a 30 to 70% concentrate in lubricating oil. This material is obtainable in several different grades of purity and derived from several kinds and viscosities of oil so that the grade employed should be chosen in view of the particular use.

The third ingredient of the present composition is an inorganic salt which is possessed'of corrosion but the principal ones to be mentioned here are borax, sodium tetra pyrophosphate, sodium carbonate, sodium chromate, sodium arsenite and especially sodium nitrite. These salts are all water soluble but are not normally soluble in oil, and the purpose of the invention is to stably incorporate them in the oil. The invention is carmanner:

is added to the sulfonate oil concentrate and otherwise course, be used but the emulsified therewith by agitation. The concentration critical, but the ratio of the inorganic compound to the sulfonate should, in all cases, be such that there is present at least a mol equivalent of the sulfonate salt for each mol equivalent of the inorganic salt. If desired, more of the sulfonate may be employed and in many cases it may be desirable to'employ as high as 4 mols of sulfonate per mol of inorganic material.

After the emulsion is formed, it is heated carefully with agitation to effect the vaporization of the water from the emulsion. This may be accomplished in open kettles or evaporators or other equipment designed for the purpose and, as the water is removed, the inorganic material .becomes thoroughly incorporated in the sulfonate in a homogeneous concentrate, which remains particular use,

of the salt in the water phase is not condition. Excessive foaming during this operation may be controlled by the addition of a known defoaming agent, e. g., an organic silicone polymer. The inorganic salt appears to be quite stably incorporated in the form of a complex and it does not settle out or precipitate while stored under normal conditions. It will be noted that in many instances the inorganic salt has a pronounced thinning action on the sulfonate concentrate. This is illustrated by a reduction in viscosity of a 50% sodium sulfonate concentrate from 660 to 290 Saybolt Universal seconds (at 210 F.) by the addition of 1.8% sodium nitrite. This concentrate can now be added to the oil base as desired along with other constituents normally employed in an oil designed for the particular purpose. Such other'constituents include oxidation inhibitors, dyes, perfumes, oiliness agents, E. P. agents, emulsifiers, detergents, pour depressants, V. I. improvers, organic bases, soaps, thickeners, coupling agents, or other ingredients as desired. The composition is then in condition for shipping to the ultimate consumer. The action of the sulfonate in eflecting the solubility of a normally insoluble inorganic salt is not clearly understood. It may be due to the formation of a mixed salt of the sulfonate and the inorganic acid but the explanation may be quite otherwise. It is suflicient here merely to recite the facts. To illustrate further the present composition and its use, the following examples may be considered:

Examr'tn I A petroleum sulfonate-inorganic corrosion inhibitor complex suitable for use in compositions of this invention was prepared as follows: 1000 grams of a 50% solution of 450 molecular weight petroleum sodium sulfonates in a paraffinic oil of 100 SUSviscosity (at 100 F.) was emulsified at 120 F. with 125 grams of a solution consisting of 25 grams of commercial grade sodium nitrite and 100grams of distilled water. One drop of an organic silicone polymer was added to controlioaming and the emulsion heated to 300 F. to

remove the water by evaporation. The resultant product (containing 2.5% sodium nitrite) was clear, stable to storage, and appreciably more fluid than the original.

EXAMPLE II When a soluble oil .is diluted with waterby the ultimate user, a stable emulsion is formed which can be employed as a metal working lubricant as mentioned above. Although satisfactory for the intended purpose this emulsion may cause serious corrosion of the machined parts, tools, and machinery. As an example of the effectiveness of compositions of our invention, the following may be cited:

A soluble cutting oil was prepared according to the'following formula:

' Soluble cutting oil Per Cent by Ingredient ight er Cernauba Wax.

Emulsions of this oil were then compared with a days.

Gooch crucible corrosion test (malleable iron filings) Corrosion Rating Emulsion w w I u a r 0 Ratio 25 1 50/1 Soluble oil 1 2-3 Soluble oil containing sodium nitrite 0 0-1 These data indicate that the soluble oil containing sodium nitrite is much more resistant to rusting than the oil which does not contain the inorganic inhibitor.

EXAMPLE III 'We have now found that such oils are satisfactorily resistant under these conditions if the sulfonate contains a suitable inorganic inhibitor such as sodium nitrite, sodium chromate, sodium arsenite or materials which act in a similar manner. This property may be evaluated by the Naval Research Laboratory Static drop test in which a drop 'of water is placed on a steel specimen immersed in the oil at F. for '1 As shown by the following data, the materials of our invention show considerable sujperiority in this-test.

Naval research laboratory static drop test [Test oil: Highly refined NEW 1oil of 43 S. U. S. viscosity at Additive g g ag 1 hour. 1 day.

No rust at 7 days.

3 days.

No rust at 7 days.

No rust at 7 days.

tra 8 No. 7 in which of sodium chromate was incorporated in the calcium sulfonate concentrate.

3 days.

No rust at 7 days.

. Example IV malleable iron filings conthe end of this time, considerable under-film corrosion had occurred. In the same test, a petroiatum containing 3% of the product of Example I afforded complete protection to the panel.

From the above examples it may be seen that our invention can be beneficially employed in the preparation of many petroleum products for use where moisture corrosion of metal surfaces is a problem. We contemplate its use in hydrocarbon fuels, lubricants for all purposes, slushing compositions, flushing oils, emulsiflable dis, greases, hydraulic media, etc.

We claim:

A composition suitable for use as a' soluble cutting oil, or the like, consisting essentially of aboutr84% mineral base lubricating oil, about 8% sodium petroleum sulfonate, about 2.5% sodiumnitrite, about 2.5% naphthenic acid, 0.4%

caustic soda, 0.9% isopropyl alcohol, 0.05% wax, and a small amount of water, said proportions being by weight.

GORDON W. DUNCAN. JOHN C. ZIMMER.

REFERENCES CITED 

